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Tumor metastasis is responsible for 90% of cancer-associated deaths, and its early detection may decrease the likelihood of mortality. Studies have demonstrated that metastasis results from the interaction between "seeds" (tumor cells) and "soil" (pre-metastatic niche, PMN). As the first and most abundant immune cells to be recruited to PMN, neutrophils play a key role in the ultimate formation of metastatic foci through mechanisms such as supporting tumor cell growth, promoting angiogenesis, and shaping an immune-suppressive microenvironment. In this study, two distinct types of sialic acid (SA)-modified liposomes were prepared to target and regulate pro-metastatic neutrophils through the l -selectin receptor. One of these liposomes, named ICG@SAL, was used to encapsulate indocyanine green (ICG) and was specifically designed for the early detection of cancer metastasis. The other liposome, referred to as ABE/Cur@SAL, co-loaded abemaciclib (ABE) and curcumin (Cur), with the intention of suppressing the progression of metastatic tumor. Fluorescence imaging results from the mouse spontaneous metastasis model indicated that ICG@SAL demonstrated faster targeting and stronger accumulation in the metastatic organs than unmodified ICG liposomes (ICG@CL). This suggested that ICG@SAL could detect tumor metastasis at an early stage. The therapy with co-loaded liposomes in the mouse experimental lung metastasis model indicated that ABE/Cur@SAL could inhibit regulatory T (Treg) cell proliferation, enhance effector T cell activity and reduce tumorigenic factor release, implying that ABE/Cur@SAL could inhibit tumor metastasis. Overall, our work provided a sensitive and convenient approach to early diagnosis and treatment of tumor metastasis. ICG@SAL could be employed for the early detection of tumor metastasis, while ABE/Cur@SAL could be used to inhibit the development of tumor metastasis when early metastasis was identified. [ABSTRACT FROM AUTHOR]

Drug-resistant Tuberculosis (TB) is a global public health problem. Resistance to rifampicin, the most effective drug for TB treatment, is a major growing concern. The etiological agent, Mycobacterium tuberculosis (Mtb), has a cluster of ATP-binding cassette (ABC) transporters which are responsible for drug resistance through active export. Here, we describe studies characterizing Mtb Rv1217c-1218c as an ABC transporter that can mediate mycobacterial resistance to rifampicin and have determined the cryo-electron microscopy structures of Rv1217c-1218c. The structures show Rv1217c-1218c has a type V exporter fold. In the absence of ATP, Rv1217c-1218c forms a periplasmic gate by two juxtaposed-membrane helices from each transmembrane domain (TMD), while the nucleotide-binding domains (NBDs) form a partially closed dimer which is held together by four salt-bridges. Adenylyl-imidodiphosphate (AMPPNP) binding induces a structural change where the NBDs become further closed to each other, which downstream translates to a closed conformation for the TMDs. AMPPNP binding results in the collapse of the outer leaflet cavity and the opening of the periplasmic gate, which was proposed to play a role in substrate export. The rifampicin-bound structure shows a hydrophobic and periplasm-facing cavity is involved in rifampicin binding. Phospholipid molecules are observed in all determined structures and form an integral part of the Rv1217c-1218c transporter system. Our results provide a structural basis for a mycobacterial ABC exporter that mediates rifampicin resistance, which can lead to different insights into combating rifampicin resistance. [ABSTRACT FROM AUTHOR]

An optical medium with abnormal dispersion supports fast light, which possesses a group velocity faster than the speed of light in a vacuum or even takes on a negative value (a backward wave), and shows exceptional promise for optoelectronic applications. In this article, three-layer dielectric waveguides composed of negative refraction cladding, which is made up of silicon crystal, and an air core are constructed, where the so-called fast light can propagate a backward wave by modifying the thickness of the air core. The dispersion properties of the fast light are investigated analytically. Finally, numerical results are derived by using the finite-element method to verify the analytical results. The proposed structure might find applications in the field of photonic integrated circuits. [ABSTRACT FROM AUTHOR]

A knowledge-aided mono-pulse forward-looking imaging algorithm to enhance the performance of airborne radar is proposed. Firstly, the ideal mono-pulse imaging model based on the dual-channel radar system is analysed and the mismatch model of the receiving channel is constructed. Then the mismatch phase error and a modified mono-pulse curve (MPC) are derived based on the least square (LS) method by taking advantage of a prior antenna pattern information. Finally, the modified MPC is utilised to perform the direction-of-arrival (DOA) estimation of each scattering centres in mono-pulse imaging. Real airborne radar data experiments are given to verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

A new degree of freedom, valley, has recently been introduced into the fields of acoustic and photonic crystals. This provides a promising platform for classical waves to mimic the valley-contrasting properties of condensed matter physics. Here, we study the plasmonic version of valley states in graphene plasmonic crystals of inversion symmetry broken honeycomb lattices. The intrinsic valley vortex feature is unambiguously revealed. The evolution of the valley chiral states involving topological transition is theoretically explored. Furthermore, numerical simulations for the selective excitations of the valley chiral states are carried out in our designed valley plasmonic crystals. Our work has potential applications in the orbital angular momentum-assisted surface plasmon polariton manipulation and the applications of plasmonic valleytronics in nanophotonics and on-chip integration. [ABSTRACT FROM AUTHOR]

Lycium barbarum L. (L. barbarum) is an economic crop with high added value and profit. Vibration harvesting is a suitable mechanized harvesting method for L. barbarum. It bruises easily during harvesting due to the softness and vulnerability of fresh ripe fruit, resulting in economic losses. This study analyzed the fruit drop and collision during vibration harvesting. High-speed photography was used to obtain the impact speed and angle of the falling fruit, and a kinematic analysis of the collision with the collection surface was conducted. The majority of the fruit had an impact speed of 3-6 m/s and an impact angle of 30-90° with the collection surface. A drop test was conducted to assess fruit bruising, and the impact speed was converted to the drop height. An orthogonal rotation experiment was conducted, and mathematical model was established between the drop height, impact angle, and impact material, and the fruit bruise rate, maximum impact force, recovery coefficient, and impact time. The effects of the factors on the fruit bruise rate, maximum impact force, recovery coefficient, and impact time were analyzed. The test results show that a vibration harvesting device for L. barbarum should be designed to reduce the height between the fruit and the collection surface and utilize a tilted collection surface and high cushioning materials to reduce the fruit bruising. This study provides guidance for subsequent research on the bruising of L. barbarum during vibration harvesting and harvester design. [ABSTRACT FROM AUTHOR]

Immunotherapy is a promising approach for preventing postoperative tumor recurrence and metastasis. However, inflammatory neutrophils, recruited to the postoperative tumor site, have been shown to exacerbate tumor regeneration and limit the efficacy of cancer vaccines. Consequently, addressing postoperative immunosuppression caused by neutrophils is crucial for improving treatment outcomes. This study presents a combined chemoimmunotherapeutic strategy that employs a biocompatible macroporous scaffoldbased cancer vaccine (S-CV) and a sialic acid (SA)-modified, doxorubicin (DOX)-loaded liposomal platform (DOX@SAL). The S-CV contains whole tumor lysates as antigens and imiquimod (R837, Toll-like receptor 7 activator)-loaded PLGA nanoparticles as immune adjuvants for cancer, which enhance dendritic cell activation and cytotoxic T cell proliferation upon localized implantation. When administered intravenously, DOX@SAL specifically targets and delivers drugs to activated neutrophils in vivo, mitigating neutrophil infiltration and suppressing postoperative inflammatory responses. In vivo and vitro experiments have demonstrated that S-CV plus DOX@SAL, a combined chemoimmunotherapeutic strategy, has a remarkable potential to inhibit postoperative local tumor recurrence and distant tumor progression, with minimal systemic toxicity, providing a new concept for postoperative treatment of tumors. [ABSTRACT FROM AUTHOR]

In this study, mesoporous carbon hollow microspheres (PCHMs) with tunable textural properties have been prepared through a facile hard template etching method. The PCHMs were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, Raman spectra, and nitrogen adsorption and desorption systems. Uniform PCHMs with shell thickness ranging from 23 nm to 55 nm are realized. PCHMs with different textural properties can regulate dielectric and electromagnetic (EM) wave absorption effectively. The composite of paraffin wax mixed with 10 wt% PCHMs (the shell thickness of PCHMs is 35 nm) exhibits a minimum coefficient value of −53.8 dB at 8.8 GHz, with a thickness of 3.4 mm. Besides, it is remarkable that the effective absorption bandwidth covers all the X band with as low as a 10 wt% filler ratio, compared with other spherical EM wave absorbers. The excellent EM wave absorption capability of PCHMs can be ascribed to the better impendence matching and strong EM wave attenuation constant based on tunable textural properties. Our results provide a facile strategy to tune dielectric properties of spherical carbon absorbers based on textural properties, and can be extended to other spherical absorbers. [ABSTRACT FROM AUTHOR]

An adaptive super-resolution imaging algorithm to enhance the performance of airborne single channel forward-looking radar is proposed. Multiple beams data to expand the processing space to enforce the sparsity of scatterers with respect to the antenna pattern was first utilised. Then, the imaging is converted into a problem of signal reconstruction with Lp-norm regularisation, and the regularisation parameter is data driven. Simulations are given to verify the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

A constant current control technique for a primary-side control system is proposed to realise high precision output current regulation. With the novel ring detect and demagnetisation portion control technique, the ending time of demagnetisation can be accurately determined and the portion of demagnetisation in a switching period remains precisely the same. The simulation results show that with this control technique, the variation of output current is less than ±1.5% of the target value. [ABSTRACT FROM AUTHOR]

Aiming at the problems of high damage rate and loss rate of the existing safflower harvesting equipment, this study designed a rotary cutting safflower harvesting end effector by combining the growth characteristics and mechanical properties. Through force analysis of the cutting tool, the key factors, which affects the harvesting performance, were clarified to be the blade inclination and the knife shaft speed. The Fluent software was used to analyze the flow field of the harvesting chamber, which aims to determine the appropriate wind speed. To improve the working performance of the rotary cutting safflower harvesting end effector, a three-factor, threelevel orthogonal test was carried out with the blade inclination, knife shaft speed and wind speed as the influencing factors, and with the recovery rate, damage rate and loss rate as the response indexes. A regression model for the three-factor interaction was developed and optimized based on the results of the Box-Behnken test. The optimal parameter combination is: the blade inclination is 15°, the knife shaft speed is 1570, and the wind speed is 6 m/s. A test of the optimization results showed that the recovery rate was 91.47%, the damage rate was 7.51%, and the loss rate was 4.67%. This study can provide theoretical basis and technical reference for the mechanized harvesting of safflower. [ABSTRACT FROM AUTHOR]

The unique cancer-associated immunosuppression in brain, combined with a paucity of infiltrating T cells, contributes to the low response rate and poor treatment outcomes of T cell-based immunotherapy for patients diagnosed with glioblastoma multiforme (GBM). Here, we report on a self-assembling paclitaxel (PTX) filament (PF) hydrogel that stimulates macrophage-mediated immune response for local treatment of recurrent glioblastoma. Our results suggest that aqueous PF solutions containing aCD47 can be directly deposited into the tumor resection cavity, enabling seamless hydrogel filling of the cavity and long-term release of both therapeutics. The PTX PFs elicit an immune-stimulating tumor microenvironment (TME) and thus sensitizes tumor to the aCD47-mediated blockade of the antiphagocytic "don't eat me" signal, which subsequently promotes tumor cell phagocytosis by macrophages and also triggers an antitumor T cell response. As adjuvant therapy after surgery, this aCD47/PF supramolecular hydrogel effectively suppresses primary brain tumor recurrence and prolongs overall survivals with minimal off-target side effects. [ABSTRACT FROM AUTHOR]

Despite recent success in islet transplantation for the treatment of type 1 diabetes, the lack of a surrogate source of donor cells that can express insulin remains a major obstacle. The present study aims to identify stem cells/progenitors directly from adult monkey islets and to assess the proliferation and differentiation potential of such cells. Our results indicate that there are pancreatic progenitor cells in the adult pancreatic islets in both normal and type 1 diabetic animals. The isolated pancreatic progenitor cells can be greatly expanded in culture. Upon the removal of growth medium, these cells spontaneously form islet-like cell clusters (ICCs), which could be further induced to secrete insulin by inductive factors. Furthermore, the secretion of insulin and C-peptide from the ICCs responds to glucose and other stimuli, indicating that the differentiated cells not only resemble β-cells but also possess the unique biological function of β-cells. In our initial autologous transplantation experiments in which ICCs were infused into the portal vein of the liver of diabetic monkeys, the elevated blood glucose levels were lowered for extended periods of time, accompanied by an increase of both insulin and C-peptide levels in the blood. This study provides a foundation for further characterization of adult pancreatic progenitor cells and autologous transplantation using pancreatic progenitor cells in treating diabetic monkeys. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of acoustic nanoscale separation via wave-pillar excitation resonance (ANSWER) as a solution to the biophysical fractionation of extracellular vesicles. Topics discussed include the challenge in developing small extracellular vesicle fractionation methods, the advantage of the ANSWER method over mechanical filtration methods, the physical mechanism of ANSWER, and fabrication of the interdigital transducers.

The article presents research report on acoustofluidic centrifuge for nanoparticle enrichment and separation. Topics include liquid droplets have been studied for decades and have recently experienced renewed attention as a simplified model for numerous fascinating physical phenomena occurring on size scales from the cell nucleus to stellar black holes; and entanglement of acoustic wave actuation and the spin of a fluidic droplet to enable nanoparticle enrichment and separation.

Aiming at SDN-based storage environment, the integrity and availability of storage service are threatened by many attacks from data plane, such as packet tampering and dropping. While existing packet forwarding verification methods to deal with the sophisticated attacks are extremely limited due to the assumption that all or part of the switches are trusted. In this paper, for the untrusted data plane, a transparent gateway-based packet forwarding verification mechanism, named GwPFV, was designed to mitigate and trace back the attacks, specially utilizing the characteristics of TCP protocol to realize a packet obfuscation method to proactively defend attacks, a fast event-counting method to find attacks, and a path switching method involved with SDN controller to locate malicious switches. Finally, both the effectiveness and security of GwPFV are analyzed in depth. The experiments performed in an SDN-based prototype storage system reveal that it can achieve the security goal with relative low performance overhead. [ABSTRACT FROM AUTHOR]

Pyroptosis is an inflammatory cell death process that is dependent on caspase. Pyroptosis is a specific form of programmed cell death with the morphological characteristics of formation of pores on the cell membrane, cell swelling, and rupture of the plasma membrane. Recent studies have demonstrated that pyroptosis plays an important role in the occurrence and development of liver diseases. Here, we focus on the mechanisms of pyroptosis, as well as on the relationship between pyroptosis and liver diseases.